1. Treatment of Integral Equations by Numerical Methods, ed. by C.T.H. Baker and G.F. Miller, Acad. Press, London 1982.
2. L. Bamberger and G. Hämmerlin: Spline-blended substitution kernels of optimal convergence. In Treatment of Integral Equations by Numerical Methods, ed. by C.T.H. Baker and G.F. Miller, Acad. Press, London 1982, p. 47–57.
3. H. Brakhage: Zur Fehlerabschätzung für die numerische Eigenwertbestimmung bei Integralgleichungen, Numer. Math. 3, 174–179 (1961).
4. F. Chatelin: Sur les bornes d’erreur a posteriori pour les éléments propres d’opérateurs lineaires. Numer. Math. 32, 233–246 (1979).
5. W.J. Gordon: Spline-Blended Surface Interpolation through Curve Networks. J. of Math. and Mech. 18, 931–952 (1969).